Performance Evaluation of the MOCO T In-Situ Combustion Project, Midway-Sunset Field

Abstract

ABSTRACT This paper describes the analytical methodology applied to the MOCO T reservoir to match 27 years of dry in situ combustion project performance. It also serves to update previous technical papers on the project. A modification of the Nelson-McNiel Analytical model is introduced that provides excellent agreement with field performance. The correlating factor derived is found to be strongly dependent upon the product of the air requirements and volume burned. Equations and graphical relationships are developed to show the recovery effects of various parameters such as air injected and volume burned. The calculated combustion front location also agrees well with produced fluid temperature maps. Close agreement between the calculated burned thicknesses and those obtained from recent seismic tomography efforts is also presented. The paper provides excess air, air-oil ratio, and oil-water ratio calculations as well as numerous graphical relationships that aided in an understanding of the reservoir, and may further improve process efficiency. These results demonstrate that analytical methods can be applied successfully to history match and predict future performance. It is believed that these results have direct applications to other reservoirs with similar parameters and characteristics.